Log files present information on events occurring in computer systems. Log files are helpful in diagnosing errors occurring in the computer system. The computer system stores log files in human-readable formats (e.g., text). Log files may store information for subsequent review by humans in repairing errors in the computer system. The computer system writes log files according to a set list of rules called a grammar. The complete grammar defines the rules of a formal language. A grammar describes how to form strings of text from the language's alphabet (e.g. alphanumeric characters) that are valid according to the language's syntax. The language's syntax is the set of rules that defines the combinations of characters that are correctly structured in the language.